A suction roll used for dewatering of sheeting e.g. for paper machines comprises a roll shell with openings and disposed within at least one suction box. The suction box is arranged stationary on the inside of the suction roll with the holey roll shell rotating around the suction box. To seal the suction box from the roll shell, said roll shell comprises lateral sealing strips which seal the inside of the suction box from the remaining volume of the suction roll, preferably in longitudinal direction of the suction roll. The suction box is delimited on both ends in peripheral direction of the suction roll by edge deckles and sealed from the roll shell.
A particular challenge in the construction or operation of suction rollers is the supply of lubrication water to reduce heat development and wear on the sealing strip.
WO 2013167656 A1 discloses the provision of a spray tube before each sealing strip used in the suction roll, in which each spray tube has its own supply line. The same is already known from DE 1005825 B of 1957. The disadvantage of the introduction in front of the sealing strip by means of additional spray pipes is the additional space requirement in the suction roll and the higher installation costs. A disadvantage of the known suction pipes within the suction zone is that they reduce the suction zone on the one hand and thus reduce the efficiency of the suction roll and on the other hand, the vacuum prevailing in the suction zone extracts a considerable amount of the lubrication water before this reaches the sealing strip.
WO 2013167656 A1 further discloses the provision of the supply of the lubricant in the sealing strip, which can also be taken from WO2014026913 (A1). The supply of the lubrication water in the sealing strip is disadvantageous for several reasons. First, the friction surface of the sealing strip is reduced by the openings of the lubrication water supply, secondly the openings of the lubricating water supply wear out visibly, thirdly the sealing strip designed as a wearing part is complex in the manufacture and thus more expensive, fourthly, the holder itself becomes more complicated, fifthly with sealing strips movable in the sealing strip holder, as they are customary according to the state of the technology, the transition from the sealing strip holder into the sealing strip is difficult, as a result of which the assembly and sealing of the lubrication water system is complex, sixthly the lubrication groove or the openings in the sealing strip can be sealed by impurities, fibers or chemicals, which would cause a local increase in wear and temperature, which in turn can lead to damage to the sealing strip or roll.